Static heat recovery ventilation system

ABSTRACT

The static heat recovery ventilation system exchanges heat, through a heat pipe heat exchanger, between stale air exhausted from a house or an apartment and the fresh air intake into the house or the apartment In a first aspect of the invention, the static heat recovery system uses a negative pressure generated by exhaust equipment inside the house or apartment, such as a bathroom fan or a range hood fan, to induce an entry of fresh air through the heat exchanger and into the house or apartment. In another aspect of the invention, the static heat recovery system uses a positive pressure in the hallway of an apartment building to induce an entry of fresh air through the heat exchanger and into a suite of apartments.

FIELD OF THE INVENTION

[0001] This invention pertains to heat recovery ventilation systems and more particularly it pertains to heat recovery ventilation systems having no moving parts.

BACKGROUND OF THE INVENTION

[0002] The lack of trade coordination during the construction of a building and the numerous duct and piping systems involved in a building could create a safety issue whereas the presence of the duct could block some of the sprinkler heads. These problems are often caused by the ducts of a ventilation system.

SUMMARY OF THE INVENTION

[0003] As a result of the experience of the inventor in this field, an innovative method has been developed to eliminate this safety issue. The heat recovery ventilation system according to the present invention does not use any dedicated fans and the duct work therefor is kept minimum.

[0004] The heat recovery ventilation system according to the present invention exchanges heat between stale air exhausted from a house or an apartment and the fresh air intake into the house or the apartment The heat recovery ventilation system according to the present invention uses the heat pipe technology which exchanges heat a thousand times faster than the standard copper pipe technology or the plate type heat exchanger.

[0005] In accordance with a first aspect of the present invention, the heat recovery system uses a negative pressure generated by compulsory equipment inside the house or apartment to induce an entry of fresh air through the heat exchanger and into the house or apartment.

[0006] In another aspect of the present invention, the heat recovery system uses a positive pressure in the hallway of an apartment building to induce an entry of fresh air through the heat exchanger and into a suite of apartments.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0007] Modern houses and apartment buildings are constructed so that they are well insulated to prevent heat loss, and have vapor barriers to prevent the infiltration of humidity inside the walls. The insulation and vapor barrier arrangement of modern houses and suites of apartments is often referred to as R2000™. To a certain extent, the modern houses and suites of apartments are airtight. This is the type of houses and suites of apartments in which the heat recovery ventilation system according to the present invention is preferably installed.

[0008] In the first preferred installation, as illustrated in FIGS. 2 and 3 in particular, a heat exchanger 20 is installed as close as possible to the exterior wall 22 of a house or a suite of apartments. The fresh air intake 24 and the stale air outlet 26 of the heat exchanger are connected to the outdoors by means of short ducts 28, 30 passing through the exterior wall 22. In the first preferred installation, the heat exchanger 20 is mounted through a partition wall 32 with the fresh air outlet port 34 extending on both sides of the partition wall. The stale air intake 36 of the heat exchanger is connected to a duct 38 extending to the bathroom exhaust fan 40 or the range hood fan.

[0009] The method of operation of the system consists of operating the bathroom fan 40 or the range hood fan to create a negative pressure inside the house or suite of the apartments. The preferred negative pressure is expressed as an external static pressure differential (EPS) with an inside pressure being lower than an outside pressure. The preferred EPS to operate the system is about 5 pascal in a house or a suite of apartments which has a chimney and burning equipment connected to that chimney. The preferred EPS to operate the system in a house or a suite of apartments that has no chimney is about 20 pascal.

[0010] It has been found that these negative pressures are sufficient to cause a circulation of fresh air from the outdoors, through the heat exchanger and inside the house or suite of apartments. It has been found that the negative pressures can induce an intake of fresh air through the heat exchanger which is sufficient to meet the health and safety requirements applicable to residential dwellings.

[0011] In the first preferred installation, the partition wall 32 though which the heat exchanger 20 is installed is a wall separating a bedroom 42 and a livingroom 44. Also in the first preferred installation, an air heater 46 may also be installed in the fresh air intake duct 28 to pre-heat the fresh air before the fresh air is introduced into the house or the suite of apartments. The bathroom fan 40 is preferably of a type which is noiseless, which is rated for a continuous operation, and which has a capacity of 50 CFM or more.

[0012] In a second preferred installation, as illustrated in FIG. 6, the heat exchanger 20 is mounted in a partition wall 52 adjacent a hallway 54 separating two suites of apartments. The fresh air inlet 56 of the heat exchanger 20 extends into the hallway 54, and includes a fire damper 58, as required by safety regulations. The hallway 54 is pressurized with fresh air from the outdoors, to generate a flow of fresh air through the heat exchanger 20 and into a bedroom 60 and livingroom 62. The main entrance door 64 to the suite of apartments has air seals to promote the flow of fresh air through the heat exchanger 20. In this second preferred installation, the stale air in the suite of apartments is also evacuated by the bathroom fan 40, or the range hood fan. 

I claim:
 1. A method for ventilating a suite of apartments having an exterior wall and a bathroom and an exhaust fan in said bathroom, said method comprising the steps of: providing a heat exchanger inside said suite of apartments, said heat exchanger having a fresh air inlet and a stale air outlet extending through said exterior wall, a fresh air outlet communicating with an inside space in said suite of apartments, and a stale air inlet connected to an outlet of said exhaust fan in said bathroom; using said bathroom fan, causing a negative pressure inside said suite of apartments and in said fresh air outlet, and causing an air circulation through said heat exchanger from said fresh air inlet to said fresh air outlet and into said suite of apartments.
 2. The method as claimed in claim 1, wherein said negative pressure is an EPS differential of about 20 pascal.
 3. The method as claimed in claim 1, further comprising the step of simultaneously discharging fresh air from said fresh air outlet into two adjacent rooms in said suite of apartments. 